Manufacture of textiles



Patented Feb. 4, 1936 UNITED STATES MANUFACTURE OF TEXTILES vLeo Waller-stein, Rowland A Gale, and Thomas G. Hawley, Jr., New York, N. Y., assignors to Wallerstein Company Inc., a corporation of New York No Drawing. Application April 26, 1934,

Serial N0. 722,504

6 Claims. (Cl. 117-2) containing or composed of natural silk in gum, it has been found desirable to have the textile fibres possess greater body during the knitting and/r .-1o weaving operation than is possessed by the final fibres or threads in the finished fabric. This is attained in the case of natural or raw silk by utilizing the silk in the condition which it is produced in nature with the filaments or strands -]5 of the silk containing the gum or bast naturally placed thereupon.

Although this gum, bast or body-giving coating, naturally occurring upon the fibres or artifically placed thereupon, is desirable during the textile forming operations, before" the textile is finished, it should be removed without disadvantageously affecting the strength, surface, appearance, or other characteristic properties of the fabric. In the case of fabrics containing natural silk with gum, it has been customary to degum the woven or knitted fabric byplacing it in a. boiling soap solution which will have the effect of removing gum, thereby preparing the fabric for such 0 other finishing operations as may be required,

as for example, dyeing, bleaching, and/or printing.

In many fabrics, however, certain threads or yarn makingup the fabric have been previously 35 processed before weaving or knitting and/or during the weaving or knitting process so that the gum thereon becomes relatively inaccessible to the dissolving action of the degumming bath.

In satin fabrics, for instance, all or part of the 40 warp threads are woven in such a manner as to extend over a great many filling threads and lie for substantial distances upon the face of the fabric in a position where they are relatively more exposed to the action of the degumming 45 bath than the'residual closely intermeshed and interwoven warp and/or weft threads;

When satin fabrics of this character are subjected to the action of a'degumming bath, the gum from the exposed overlying portions of the 50 warp threads will be more readily removed, while the gum from the intermeshed and interwoven residual warp and weft threads will be relatively slowlyremoved. As a result, these overlying threads are necessarily subjected to an excessive 55 amount of treatment in the degumming bath in In the. production of manytextile materials, andparticularly in the case of textile materialss order that the fabric as a whole shall be completely degummed.

In the case of certain crepe weaves also the Weft or filler threads are relatively highly twisted, whilethe warp threads have a relatively low 5 amount of twist. Whena crepe fabric of this character is subjected to the degumming bath, the warp threads where exposed are readily degummed, whereas the higher twisted weft or filling threads and portions of the warp threads are only relatively slowly degummed, as a result of this difference in accessibility to the degumming solution. The warp threads in this case also will be over-treated and consequently damaged or rendered liable to damage in the degumming solution before the twisted weft or filling threads are completely degummed.

Again in the case of yarns for forming knitted fabrics, particularly in forming stockings, certain of the strands making up the final knitting yarn 2 have sometimes been given a relatively high twist, while other strands are given a relatively low twist or substantially no twist at all. In this instance, again, the untwisted or low twist strands will be degummed at a much faster rate than the relatively highly twisted strands.

It is the plan of-the present invention to so prepare textile fabrics containing natural silk in gum, that the various filaments, threads or fibres of silk in gum making up thesame will be degummed in more nearly the same time periods,

thus eliminating the need of over-treating one portion of the fabric because of the difficulty of degumming another portion. a

The object is to prepare an improved textile crepe fabric, having a relatively untwisted or low twist warp and a relatively high twist filling or weft which may be degummed in a relatively shorter time without necessitating a long boiling period due to the relative inaccessibility of the gum on the highly twisted weft or filling threads.

Another object is to prepare a satin fabric, preferably containing in whole or part natural silk in gum which may be subjected to degumming treatment without the overlying warp threads being disadvantageously affected due to their accessibility by reason of any extended treatment necessary because of the relative inaccessibility of thefilling or weft threads.

Another object is to provide twisted yarns for knitting and for other purposes in which, although the various fibres making up the yarn have different amounts of" twist; it will not be necessary to over-treat'these threads of relatively low twist, the gum of which is relatively accessible to the degumming action in order to secure satisfactory degumming of the threads of relatively high twist, the gum of which is not readily accessible.

Other objects will appear during the course of the following application.

According to the preferred embodiment of the present invention, it has been found desirable to prepare the yarn or fibres which are to be so processed or placed in the fabric that their gum or best is relatively inaccessible to the degumming bath, that they maybe degummed at more nearly the same rate as theyarn or fibres, which are so processed and/or placed in the fabric that their gum coating will be relatively accessible.

As a result when some fibres are twisted and/or so interwoven in the fabric that their gum coating will be less accessible than the gum coating or the other strands, fibres or yarn, the degurnming action will take place at a more uniform rate, with the result that both the inaccessible and accessible fibres, strands, or yarn, will be degummed in the fabric at more nearly the same rate without the need for over-treating the accessible fibres with its accompanying disadvantageous eil'ects:

According to the present invention, it has been found most suitable and desirable to resort to an impregnation of the yarn before twisting, knitting and/or weaving with a proteolytic enzyme preparation under such conditions, as not to degum the yarn.

Among the preferred enzyme preparations are those prepared i'rom plants and/or by the growth cl certain bacteria, lungi, and other similar organisms.

It has beeniound most suitable, especially in use oi plant enzymes, such as papain, to use activstcrs. such as sulphur compounds or cyanldes.

with enzymes oi bacterial origin, it has been round suitable to add sodium and potassium carbonstes or bicsrbonstes, or mixtures thereoi.

It is an essential ieature'oi the present invention that the natural sill: in gum before being ubjected to any textile operations. -such as twisting, knitting, and/or weaving, be impregnated with the enzyme without being substantially degununed. The degumming operation is only carried out alter the enzyme impregnation and may be carried out without the utilization oi any additional proteolytic enzyme preparations and alter the goods have been nnally woven and knitted and are being subjected to or about to be sublcoted to nnishing operations.

the prclerrcd procedure, the natural silk in yarn or skein term, is dipped into a bath or a temperature below 50 6., said both containing in solution and/or in suspension the proteolytlo ensyine preparation with which may be preferably combined the alkali. metal salt or salts or a high molecular weight iatty sold or fatty acids, or the alkali metal salts oi sulphuric or sulpllonic acids oi aliphatic aromatic, and/or slicyclic comol high molecular weight and/or sulchonsied oils and raw oils. 7

smog the wetting out compounds which may be used are soaps such as sodium cleats, sodium palinitetc, sodiuni' stearete, sodium hexadooyl sulionate, and so iorth; and sulphcnstsd oils such as sulshcnated olive oil, sulphonstod castor oil and sulphcnsted ccccanut oil.

79 this bath is preterably also added a raw oil as ior example nost'moot oil. olive oil, or other aoaaoes similar vegetable, mineral or animal oils and so forth.

The skein or yarn may be suspended in the soaking bath for a suflicient length of time to assure that the enzyme preparation and the other 5 ingredients have thoroughly penetrated the gum in the silk, and at all times the temperature and pH should be so maintained that substantially no degumming action results.

llfhissoaking may be carried out from minutes to"16 hours and it preferably should not be carried out for longer than 24 hours. The skein -or yarn after being so impregnated with the enzyme preparation is centrifuged so as to remove excess moisture and then is partly or thoroughly dried before being subjected to further textile forming operations.

Various protease preparations may be used in carrying out the process, such as protease preparations derived from micro-organisms which under suitable culture conditions develop proteolytic enzymes, as, for instance, preparations derived from aspergillus oryzae, and/or from cultivation of bacteria, such as belong to the group of mesenterlcus or subtilis. Other suitable proteolytic enzymes may be used, such as papaln, trypsin, pancreatin, or pepsin. Suitable mixtures of the described enzymes may be used.

As examples in carrying out our process, we may proceed as follows:

Example 1.l00 pounds of raw silk are soaked from 80 minutes-to 1 hour in a bath or solution consisting of 400 pounds of water in which have been dissolved 50 poundsof the bacterial enzyme preparation, 1 pound or sodium sulnte or sodium bicarbonate for eilecting a suitable pH, and 1 pound oi sulfonated oil, this latter material being used to effect a better penetration, or as it is technically called, a wetting-out oi the fiber, though it will be understood that other penetrants can be used for effecting this wetting-out, such as a small amount of soap. Other suitable pH regulators, lor instance, sodium carbonate, or a mixture of both may be used instead of the sodiiun sulilte referred to.

Soaps and emulsions or common soaking oils, such as host's-root oil may also be used in con- Junction with enzymes. The temperature at which this process is carried out may be advantageously varied with the time consumed in the operation, the nature or origin 01' the silk, the nature of the particular enzyme employed, and the presence of other constituents, such as pH regulators. However, we generally employ this was; at room temperature, that is, from 60 The silk is then removed from the enzyme bath and the adhering liquor is removed in any suitable manner, as by centrifuging, and alter the centrifuging step the silk i'lbers are dried at a low temperature by an air blast or any other suitable method.

llcomple 8.-l00 pounds of 18/18 Japan white sill: in the gum are soaked tor 80 minutes at room temperature in 400 pounds of a water solution containing! pounds oi pepsin, 4 pounds of sullonsted oil. 0.05 pounds of potassium cyanide, 2 pounds of mono-sodium phosphate. It is then centrifuged and air dried.

Ecamplo .l.l00 pounds of 18/15 Japan white sills in the gum are soaked lor 30 minutes at room temperature in 400 pounds oi a water solution containing} pounds oi ponoreetin, and 1 pound oi sodium lultlte or sodium bicarbonate and suit- 7 able penetrants and/or 2,029,9ea' j, I 3

8 to 16 hours orovernight and the amount of theenzyme preparation may be cut in, half. The pH of the impregnating baths is'preferably regulated at'all times to be between4jand 10 and temperature to between 60 and 90 I After the silk has been impregnated'in this manner without any substantially visible effect.

upon thegum, the silk may be processed'by winding andtwisting, and it may be subsequently woven either alone or with other materials.

For example, the silk 'skeins so, impregnated may be processed into a highly twisted silk yarn containing between to 80 turns. Thisyarn is to beutiliz'ed for'the filling ofv crepe fabric having. a relatively untwisted warpwhich has: not

been so impregnated. Withsuch a crepe fabric.

when subjected to a treatment in a hot or warm degumming bath, it has been found that not only may the crepe fabric be degummed atasubstantially rapid rate and in a much shorter time than a similar fabric in which'the twisted filling has not been previously impregnated, but in addition the resultant fabric is of improved quality being whiter and having no appreciable chafing or damage. 1

With a satin fabric on the other hand the filler may be conveniently previously impregnated, as above described, while the relatively accessible and exposed overlyingstrands are not impregnated. Where part of the backing has been relatively highly twisted, while another portion of the backing is either untwisted oronly of low twist character, the former may have been'subjected to an impregnation at a greater concentratiorv or for a greater length of time with the same preparation as above described, while the latter may be subjected to a lesser enzyme concentration or to treatment in the soaking bath for a lesser period of time. As aresult of this treatment the various strands of the satin fabric will degum at more nearly the same rate, permitting the entire degumming operation to take place in a shorter time and produce a much higher qual ity fabric.

As a general rule, when fabrics contain relatively accessible and inaccessible strands and filaments, the inaccessible strands of which have been impregnated with an enzyme preparation, as above described, they may be degummed, in many instances in about half the time to quarter the time offabrics in which neither the inaccessible nor the accessible portions thereof have been subjected to such impregnation.

As above indicated, where diflerent portions in the fabric have relatively different degrees of accessibility in respect to the decoating-or degumming bath, the fibres making up the different portions may be differentially impregnated with the enzyme preparation either inrespect to time or concentration so that in the final deccating or degumming bath the process will take I place in a more rapid fashion without over-treatment of any particular portion of the fabric.

To give several examples of the degumming of fabrics which have been differentially impregnated according to the present invention:

Example 1.-A crepe back satin is formed of a warp consisting of 20-22 yellow japan silk in single threads not twisted together and not treated with proteolytic enzymes, which are woven so as to lie predominantly on the surface of the fabric; and'of a filling or weft consisting of threads of 13-15 whie japan silk which have been treated with proteolyticenzymesand which also have been twisted together.'{ In the-filling, thesingle threads, after having. been treated withan enzyme preparation and dried are twisted together, eleven at a'time, toa twist of fifty turns per inch.

These compositestrands are. woven with the twist strands. V

The woven fabric is degummed by immersion .warp using alternately. two right and two left in a solution containing 150. lbs; of soap and 150 lbs. of sodium sulfite in.2,000

gallons of water at a temperature of208-212 1?. a.

Satisfactory degumming without chafing of the fabric results in one hour.

.In the case of a fabrieof identical'construction, but whlchgthe filling-thread: were not especially prepared withv enzymes, as outlined above, two hours treatment in thev degumming solution. was required and the resulting fabric showed definite defects due toehafing of the exposed warp threads; a

Example 2.-'-A fiat crepe is formed'of a warp consisting of 2022 yellow japan silk single threads, 324 per inch, not twist dmndnot treated withproteolytic enzymes; and of a filling or weft consisting of 2 right and 2 left hand. twisted threads woven alternately at 56 threads per inch. The threads were made by twisting together three threads of 13-15 white japan silk which had been impregnated with a proteolytic enzyme preparation. They were twisted 60-65 turns per inch.

The fabric was degummed in a boiling 2% soap solution in 15 minutes. It was white in appearance and soft. The corresponding fabric made without the proteolytic enzyme treated silk required'over 40 minutes boiling in 2% soap-solution for complete degumming. Its appearance was 'of a yellowish cast.

By the expression inaccessible fibres as contrasted with accessible fibres,'or by similar expressions applied to filaments, strands, yarn, and so forth, is meant those fibres having a bodygiving coating, whether of a protein, carbohydrate, and/or fatty character, which have been processed or positioned in such a manner in the final fabric that they are relatively inaccessible to the'action of degumming or decoating solutions. I This inaccessible positioning or locationing of the coating is usually caused by the processing of the fibres, strands, filaments, and/or threads carrying the coating, particularly by twisting or by interlacing, interweaving, and/or interknitting such filaments, strands, and fibres that their coatings are relatively inaccessible as contrasted to the coating of other fibres in the fabric.

The present application is a continuation in part of application Serial No. 606,286, filed April 19, 1932 and is similar in subject matter to copending applications Serial No. 722,505 to 722,- 508 all inclusive, filed April 26, 1934,-all of which applications are being issued concurrently on" fabric are in relatively inaccessible condition, while others are in accessible condition to the action of a subsequent decoating' bath, which comprises impregnating these fibres, the coatings of which are relatively inaccessible with a proteolytic enzyme preparation without removing said coating, drying said impregnated fibres, combining said impregnated fibres nated'fibres,'the coatings-of which are relatively accessible to form a fabric.

2. A process of forming crepe silk fabrics of natural silk in gum, which comprises impregnating the filling yarn with a proteolytic enzyme preparation without removing said gum, dehydrating said impregnated yarn, highly twisting this filling'yarn and then weaving .this highly twisted yarn with a relatively untwisted unimpregnated warp yarn.

3. A process of preparing satin fabrics of natural silk in gum," which comprises impregnating the filling yarn with a proteolytic enzyme preparation without'removing said'gum, dehydrating said impregnated yarn, and weaving such impregnated yarn together with unimpregn-ated textile fibres making up the overlying warp.

4. A process of preparing satin fabric of nat- V ural silk in gum with a twisted filling yarn and an untwisted overlying warp yarn which comprises impregnating the filling yarn before twisting with a proteolytic enzyme preparation with out removing said gum, dehydrating said imwith unimpreg pregnated yarn and weaving such impregnated yarn together with unimpregnated textile fibres making up the overlying warp.

5. A process of making fabrics of composite twisted yarns, of natural silk in gum, in which some of the strands are relatively highly twisted while other of the strands are relatively lowly twisted or untwisted, which comprises previously impregnating those strands, which have been relatively highly twisted with a'proteolytic enzyme preparation without degumming, drying the impregnated strands, and then combining said impregnated strands with the unimpregnated strands of relatively low twist or untwisted to foam a textile fabric therefrom.

6. A textile fabric composedof a plurality of interconnected fibres composed of natural silk in the gum, some of which fibres have been so 

